NUTRITION  [ back to Recovering from a Brain injury ]
The old saying "you are what you eat" is particularly true of the brain. The solid matter of the brain is composed 60% of fats, primarily the soft, flexible fats known as phospholipids. These are used to build the selectively permeable cell walls of neurons, the myelin sheathing which coats the axons and the receptor sites on dendrites and cell membranes. Key components of these phospholipids are the "essential fatty oils" (Omega 3 and Omega 6) which our bodies are unable to manufacture, and must be taken in through food consumption. Nutritional research shows that for most of human history, our ancestors ate a diet that was rich in Omega 3s and well balanced between Omega 3s and Omega 6s. The Stone Age diet was high in lean meats (from wild game), nuts, fresh fruits and berries and oily, cold water fishes, nature's most concentrated store of Omega 3. These contributed to healthy, efficient brain function, because Omega 3 oils remain softer and more flexible than any other fats at body temperature. The human brain evolved on that diet.

Ever since the Industrial Revolution in the 19th century, our diet has become increasingly depleted of essential fatty oils. As discussed below, this has been linked with the dramatic increase in "neurodegenerative" disorders such as Parkinson's, Alzheimer's and other dementias; with cerebro-vascular disorders like stroke; and with depression. Our anxiety about heart attack prevention, has led many people to go on fat free diets that sacrifice brain health. Eating the right fats in the right amount is critical to brain health and prevention of degenerative brain disease.

The Atkins Diet Revolution has properly reminded us that a high carb, low fiber diet causes big spurts of insulin to convert sugar to stored fat and make us obese. However, brain cells live on glucose, which is the form that sugar takes in our blood. In fact, 99% of the energy our brain needs to operate comes from glucose. Of all brain processes, memory is one of the most consumptive of sugar, and the hippocampus (the portion of the inner temporal lobe that consolidates long term memories) is a huge sugar guzzler, as we know from PET scans. Although the brain weighs just 3 pounds, it consumes about 25% of all the sugar we metabolize in our bodies. A paper in the Feb. 2003 Proceedings of the National Academy of Science by Antonio Convit of the NYU School of Medicine, shows that diabetics, the obese and others with impaired glucose tolerance have memory difficulties on testing. Exercise and weight control can stave off obesity and diabetes for many people. However, no matter how lean you are, it is critical to take in daily sources of complex carbohydrates to keep your brain energized. Whole fruits, orange juice with pulp, vegetable juices and whole grain breads, cereals and pastas are all good sources.

Do we eat too much? Our ancestors did not have to worry much about portion control because they could not store sufficient excess food to over consume. They engaged in "caloric restriction" without knowing it. Recent research by the National Institute on Aging shows that deliberately restricting the daily caloric intake of rats slowed age-related atrophy of their brains and protected them against destruction of brain tissue by neuro-degenerative diseases. Older rats on restricted caloric intake also performed better on tasks of learning, memory and coordination. This suggests that we eat less and eat smarter.

There are no shortcuts. Thanks to the Hatch Act of 1994 the US government completely de-regulated dietary nutritional supplements (DSNs). Ever since, the makers of DNSs have legally been allowed to claim they improve concentration, memory, mood and other brain functions without having to prove by controlled clinical research their additives are efficacious or safe for human consumption in the amounts recommended. The makers of DSNs do not have to ensure or prove that each batch is of identical quantity, quality, purity or potency. A survey by NPR, the Kaiser Foundation and Harvard's Kennedy School in 1998 showed that half of all adult Americans believe these non-drug substances are generally good for them and do not pose a health hazard. Unfortunately they are making themselves human guinea pigs in an uncontrolled experiment on the public. Dietary nutritional supplements are now ubiquitous. Not just in pill bottles, but in drinks, baked goods, breakfast cereals, etc.

With each passing day, newspapers are reporting more and more cases of illness, sometimes fatal, associated with DSN use. According to the Dana Forum on Brain Science, there is no scientific evidence that ginko biloba staves off age associated cognitive decline, but gingko can cause bleeding and while St. John's Wort may help persons with the mildest form of depression, persons with severe depression place themselves at risk of suicide by taking it instead of getting medication and counseling from a psychiatrist. Even vitamins can be harmful when taken in excessive quantities. A 3 decade study of vitamin A consumption in Stockholm, Sweden published in JAMA in Jan. 2003 incidates that taking more than 1.5 milligrams of Vitamin A a day causes bone weakening with high risk of fractures. Persons with TBI who have vertigo or balance problems and who are at risk of falling need strong bones, and should limit consumption of Vitamin A to less than 1 milligram a day.

There is no substitute for good nutrition. Brain cells were designed to communicate through the rapid release of neurotransmitter substances in response to a stimulating event, e.g. releasing noradrenaline when the cave man noticed a charging woolly mammoth, enabling him to to run top speed across a field of sharp rocks without concern for his lack of protective footwear. For this process to occur as intended, the brain chemicals released from the axon tip of one brain cell must attach to or dock with receptor sites on the dendrites, dendritic spines or cell membranes of other brain cells. This requires a lock and key fit. The receptors must physically accommodate the unique shapes of the various neurotransmitter molecules which shower down from axon terminals to dendrites in milliseconds. Long term retention of new information and new skills involves not just strengthening of synapses but physical modification receptor site structure to facilitate nerve cell firing in the presence of a selected stimulus. Our modern diet, so high in saturated fats, supplies our brains with fats which are relatively hard and rigid at body temperature, making neurotranmission less effective, because fewer neurotransmitter molecules can bind to receptor sites.

Researchers at Case Western Reserve University School of Medicine have analyzed the eating pattern of 304 elderly men and women, 72 of whom developed Alzheimer's Disease (AD). In a report issued in July 2000 they noted finding that consumption of a high fat diet between the ages of 20 and 60 led to a significant increase in the incidence of AD. They defined a "high fat diet" as one in which 40% or more calories consumed each day came from bad non-Omega 3/6 fats, and which was deficient in fruits and vegetables. As to persons with the common genetic mutation (the apoe-e4 gene) the increase was 8 fold for the persons who ate the high fat diet. As between persons with the apoe-4 mutation who ate a high fat diet vs. those without the mutation who ate a low fat diet, the increase in the risk of AD was 23 times!

The explanation they set forth is that the apoe gene is involved in the transport of lipids through the bloodstream to the brain, and the more "bad" fat it transports, the more material which can be converted in the brain to "free radical" substances such as the sticky beta-amyloid proteins which clump in and around brain cells to cause AD. Bad fat, as further discussed below, contributes to neuro-degenerative disease and inefficient transmission of chemical messages in the brain with resultant depression and poor memory.

In January 2001 biology professor Julie Conquer of the University of Guelph in Toronto published a study showing a link between Alzheimer's and the fatty acid DHA (docosahexaenoic acid) from cold water fish. She studied 70 elderly residents of Toronto, 75% normal and 25% of whom had Alzheimer's She found that the Alzheimer's group had 30-40% less DHA in their blood than normal, non-demented seniors. Red meat has no DHA. Professor Conquer recommends either eating a lot of cold water fish or taking DHA supplements. She took them during and after her 3 pregnancies to ensure adequate brain development in her kids. A study the following year in the British Medical Journal found that elderly people who ate seafood (a rich source of DHA) just once a week had 44% lower risk of being diagnosed with dementia and 31% lower risk of being diagnosed with Alzheimer's than a cohort group of elderly people who ate lots of meat and no fish. See, BMJ 2002 Oct.26;325:932-3.

The term brain plasticity is not just a metaphor for the capacity of the brain to alter its own circuitry in response to experience. It is literally true that the fat composition of neurons and their extensions must be sufficiently plastic (in the sense of malleable or easily sculpted) for memory, new learning and brain repair to occur. The agrarian revolution radically changed the Stone Age diet. Once nomadic bands of hunter-gatherers settled down and built cities, they phased out the old foods rich in Omega 3s and well balanced between Omega 3s and 6s for wheat, rice, corn, fatty beef, fatty poultry and dairy products like milk, butter, cheese, sour cream and yogurt. Our diets became still more deficient in Omega 3s and good balance between Omega 3s and 6s with the food processing techniques which followed the Industrial Revolution. These include de-husking wheat and rice for longer shelf life, but leaving behind a polished grain devoid of fiber and nutrients is left; replacing butter which spoils easily with products that have long shelf life like margarine (a trans-fatty acid) or hydrogenated palm, linseed and coconut oils for baking; and replacing unsaturated olive oil and flaxseed oil with saturated oils (sunflower, safflower, corn) for cooking and salad dressings.

Hydrogenated oils are solid at room temperature and have a long shelf life, but they go rancid in the presence of oxygen at body temperature, generating free radicals which damage cell membranes and precipitate inflammation. New studies implicate onset of Alzheimer's and other degenerative brain diseases with high intake of bad fats like hydrogenated oils in susceptible individuals. Not only have we - as a society - vastly increased our intake of dietary sources of toxic, free-radicals, but we have stopped eating anti-oxidant food substances which protect our brain cells and other cells from the destructive effect of free radicals. Our dietary change over has depleted fiber, Vitamin E, trace minerals like selenium and other anti-oxidants, with a dramatic rise in cancers of the lung, breast, colon and other organs. With the dawn of the fast food diet, we are taking in 80% less Omega 3s than our ancestors. Foods high in Omega 6 fatty acids include potato chips, french fries, ice cream, milk shakes and pizza cheese, foods cooked in safflower oil or processed with hydrogenated oils (Twinkies). They become hard and rigid in the human body. Their Omega 6 fats clog the arteries, block the flow of blood and oxygen to the brain and heart, raise blood pressure and cause fatal strokes and heart attacks.

Omega 3 and Omega 6 are used by the body to make different types of prostaglandin hormones which affect cell growth, immune function, blood clotting and other critical functions. In general, the Omega 6 derived prostaglandins promote inflammation, clotting and scarring; while the Omega 3 derived prostaglandins do the opposite. We need both in the right balance to keep each other in check. The body is a homeostatic (self-maintaining) system. A healthy body balances the two, which should be consumed in near equal proportions. Too much Omega 6 and too little Omega 3 will produce illness.

Omega 6 (linoleic acid) is readily converted to ARA (arachidonic acid) in the body which plays a major role in destructive inflammatory processes including cancer, heart disease, stroke and arthritis. A diet high in Omega 3 can block this conversion and protect us against those diseases. Nutritional research shows that people who eat foods high in Omega 6 and low in Omega 3 fatty acids display slowed cognition and reduced memory capacity. Our ancestors ate a diet with a Omega 3 to Omega 6 ratio of 1:1, yet today most of us eat a diet with a ratio of between 1:20 and 1:30. This diet makes us dumber. It also makes rats dumber. Rats fed a high Omega 3 diet show better memory, greater ability to navigate mazes, larger brains and more synapses. Rats fed Omega 3 deficient diets had smaller brains, fewer synapses and showed less intelligence and memory. It turns out that insulin boosts cognitive capacity, but more and more Americans, at increasingly early ages, have become insulin resistant and diabetic. Diabetes is a direct assault on our nervous system, and is associated with the death of nerve cells from excess blood sugar. Diabetic suffer from cognitive impairment including memory loss, and so do insulin-resistant people in a pre-diabetic state. Reducing our intake of bad fats makes us more sensitive to insulin, which is necessary to normalize glucose levels in the blood and prevent diabetes.

Memory is not the only brain process dependent on neurotransmission. All brain processes utilize it, including regulation of mood. There are numerous studies showing that a diet rich in Omega 3 can so improve the functioning of people suffering from bipolar disorder and major depression as to enable them to leave the hospital. Other studies show that a diet high in flax oil can achieve nearly as good a result with these patients. It is established that high intake of bad fat with low intake of good fat is linked to depletion of serotonin and depression. In May 2000 psychiatrist Antti Tanskanen of Finland reported to the American Psychiatric Association that people who frequently eat fish have 30% less risk of developing depression, because of their higher intake of Omega 3 fatty oil. In June 2000 at the National Institute of Food Technologists, Dr. Joseph Hibbeln of the National Institute of Alcohol Abuse and Alcoholism stated the incidence of depression in our society has increased 100 fold in tandem with a decline of consumption of Omega-3 fats in our diet. He referred to the Finnish study as well as a recent study of 200 elderly persons in Iowa who exhibited a high degree of depression and a deficiancy of omega-3 fats.

Health authorities in the field of nutrition such as Andrew Weil, M.D. and Jean Carper, agree that foods rich in Omega 3 rich boost immune function, reduce inflammation, promote healthy skin and hair, normalize bowel function, stabilize mood, sharpen memory and improve our capacity for new learning. So, how do we get more Omega 3 in our diets, and knock the ratio of Omega 3 to Omega 6 back down towards 1:1?

Health authorities encourage the following dietary changes. For those of us who can stomach cold water fish, work in as much salmon, herring, mackerel and sardines as possible, as they are richest in DHA (docosahexaenoic acid), the longest chain Omega 3 and the very best for your brain. For people who cannot bring themselves to eat that much fish, there are fish oil supplements in capsule form or you can take 1-2 tablespoons of flax oil a day. Flax oil is high in the shorter chain Omega 3 oil known as ALA (alpha linolenic acid). Other foods rich in ALA are flax seeds, wheatgerm (which is also high in Vitamin E), dark green leafy vegetables, walnuts, chestnuts, pumpkin seeds, purslane, walnut oil and fortified eggs. Cook with olive oil rather than corn or safflower oil. Eat more fresh fruit and less cakes, donuts and sugary pastries. Switch from whole to skim when consuming milk, yogurt or cottage cheese. Avoid or reduce intake of pizza cheese, ice cream and fatty meats. Eat as much salad and raw, unsalted nuts as possible. Brazil nuts are delicious and high in selenium, an essential anti-oxidant. Other excellent sources of anti-oxidants are tomatoes, cantaloupes, watermelon, peaches, spinach, broccoli, cabbage, kale and chard. Anti-oxidants protect the brain from and can mitigate the effects of toxic chemicals (free radicals) released during stroke or brain trauma.

So what is the relationship between TBI and nutrition and why should people living with a TBI care about nutrition? By killing and damaging brain cells (the factories which make neurotransmitters) and disrupting the synapses where neurotransmitters are exchanged, TBI reduces the amounts of neurotransmitters which reach their targets. As a consequence the person with a TBI experiences slowed cognition, impaired memory, depression, apathy and irritability. Someone with a TBI can least afford to eat lots of bad fat and little good fat, because all of those problems will be compounded. A person with a TBI should take the best possible care of himself and give his brain every bit of extra help, including nutritional help, it needs to recover and resume normal function. A diet which is high in Omega 3, which balances intake of Omega 3 and Omega 6, which avoids excess sugar and starch, and which is high in anti-oxidants, will maximize the function of the brain cells spared by the trauma, and promote the healing and recovery of damaged cells. Brain trauma disturbs cell membranes, making them extra-vulnerable to attack by free radicals. Reducing intake of Omega 6 foods and increasing intake of anti-oxidants will protect the membranes of your brain cells during this crucial recovery period. Taking good care of your car means using good oil and changing it frequently. The same is true for the care of our brains. Research indicates that concussions can dramatically raise the risk of Alzheimer's Disease in people with the APOE-e4 gene. Since high Omega 3 is protective against AD, and a high Omega 6/low Omega 3 diet is implicated in development of AD, err on the side of caution after a concussion and change your diet to give yourself more protection against AD instead of encouraging it with high intake of bad fats.

Remember that smart nutrition is just one key to optimal recovery from a TBI. Survivors must also get regular cognitive stimulation and physical exercise, long periods of sleep and pleasant social experiences - even a daily walk with a friend or family member. You must also learn how to manage the stress associated with the recovery phase. During recovery you will experience cognitive slowing, poor short term memory, fatigue, reduced endurance, frustration and tearfulness. A neuropsychologist and a TBI support group can make a huge positive difference in how you respond to, and how you handle, these difficulties. With a positive attitude, and a future-oriented outlook (rather than a past-oriented focus on what one has lost), the odds of good recovery improve significantly.